A wireless data terminal device may also be referred to as a mobile broadband (MBB) device. It may be a portable WI-FI device or a wireless data card device. Further, the wireless data terminal device may receive a radio signal sent by a base station (for example, an Long Term Evolution (LTE) network signal or a Universal Mobile Telecommunications System (UMTS) network signal), and convert the signal sent by the base station into a signal used for Internet access of user equipment.
In some other approaches, a data transmission scheme used for communication between the wireless data terminal device and a user-end Internet device (which may also be referred to as user equipment) is fixed. However, a wireless network environment in which the wireless data terminal device is located is complex. The wireless environment varies when the wireless data terminal device is at different locations. The wireless data terminal device cannot adjust the data transmission scheme at any time. Therefore, user experience is affected.